<!DOCTYPE html>
<html lang="zh_CN">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>

</body>
<script type="text/javascript">

    console.log(Math.floor(1.23));// 向下取整 1 找一个比自己小的最大的整数

</script>

</html>
